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Frequently Asked Questions for the Eclipse Triquetrum project.


What is a triquetrum, anyway?

TriquetrumDreistab 00-128px.jpg

"The triquetrum (derived from the Latin tri- ["three"] and quetrum ["cornered"]) was the medieval name for an ancient astronomical instrument first described by Ptolemy (c. 90–c. 168) in the Almagest (V. 12)" (Source: Wikipedia)

Pictured is the triquetrum of Copernicus from Meyers Großes Konversations-Lexikon 6. Auflage 1905–1909.

The Eclipse Triquetrum project uses Ptolemy II as its execution engine and the Ptolemy II icon shows Ptolemy holding a triquetrum. The name also evokes the model-view-controller pattern.

How is triquetrum pronounced?

We asked a Latin teacher for the proper pronunciation, who stated that the correct Latin translation is the same as the second English option in this video: tri-QUET-rum, not tri-QUEET-rum

What is the relationship between Triquetrum and Ptolemy II?

Triquetrum uses Ptolemy II as Triquetrum's execution engine. For details about Ptolemy II, see, which states:

"Ptolemy II is an open-source software framework supporting experimentation with actor-oriented design. Actors are software components that execute concurrently and communicate through messages sent via interconnected ports. A model is a hierarchical interconnection of actors. In Ptolemy II, the semantics of a model is not determined by the framework, but rather by a software component in the model called a director, which implements a model of computation."

What is the relationship between Triquetrum and Kepler?

Ptolemy II is the execution engine used by both Triquetrum and the Kepler Scientific Workflow System. We see Triquetrum as a possible way forward for Kepler to use a more common build infrastructure and to otherwise leverage the Eclipse ecosystem. One of the goals of Triquetrum is for Triquetrum to be able to open at least some Kepler models.

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